全文获取类型
收费全文 | 90篇 |
免费 | 19篇 |
国内免费 | 14篇 |
专业分类
化学 | 3篇 |
力学 | 2篇 |
综合类 | 2篇 |
数学 | 9篇 |
物理学 | 107篇 |
出版年
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2018年 | 1篇 |
2016年 | 2篇 |
2015年 | 7篇 |
2014年 | 9篇 |
2013年 | 8篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 9篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 9篇 |
2004年 | 3篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1989年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
排序方式: 共有123条查询结果,搜索用时 31 毫秒
41.
In this paper, we investigate the thermodynamics of the global monopole anti-de-Sitter black hole in the grand canonical ensemble following the York's formalism. The black hole is enclosed in a cavity with a finite radius where the temperature and potential are fixed. We have studied some thermodynamical properties, i.e. the reduced action, thermal energy and entropy. By investigating the stability of the solutions, we find stable solutions and instantons. 相似文献
42.
We consider GUT models inspired by recent local F-theory constructions. We show that after switching on vevs to scalars the extra matter becomes messengers. We discuss conditions on these vevs under which the models do not lead to unacceptable baryon/lepton number violating processes. 相似文献
43.
44.
Circular geodesics and accretion disk in the spacetime of a black hole including global monopole 下载免费PDF全文
We study circular time-like geodesics in the spacetime of a black hole including global monopole. We show that when the range of parameter changed the properties of the circular geodesics and the radiation of accretion disks are different. It follows that the properties of the accretion disk around black hole including global monopole can be different from that of a disk around Schwarzschild black hole. 相似文献
45.
本文及后继三篇文章在电磁学和电动力学框架内分别介绍磁单极的若干奇特性质.针对由一个磁单极和一个点电荷构成的体系,首先证明这个体系的电磁场角动量具有极简洁的表达式并讨论可能的电荷量子化,然后显式地演示体系角动量的转化与守恒. 相似文献
46.
A multiple monopole (or multipole) method based on the generalized mul- tipole technique (GMT) is proposed to calculate the band structures of scalar waves in two-dimensional phononic crystals which are composed of arbitrarily shaped cylinders embedded in a host medium. In order to find the eigenvalues of the problem, besides the sources used to expand the wave field, an extra monopole source is introduced which acts as the external excitation. By varying the frequency of the excitation, the eigenvalues can be localized as the extreme points of an appropriately chosen function. By sweeping the frequency range of interest and sweeping the boundary of the irreducible first Brillouin zone, the band structure is obtained. Some numerical examples are presented to validate the proposed method. 相似文献
47.
A numerical method, the so-called multiple monopole (MMoP) method, based on the generalized multipole technique (GMT) is proposed to calculate the band structures of in-plane waves in two-dimensional phononic crystals, which are composed of arbitrarily shaped cylinders embedded in a solid host medium. To find the eigenvalues (eigenfrequencies) of the problem, besides the sources used to expand the wave fields, an extra monopole source is introduced which acts as the external excitation. By varying the excitation frequency, the eigenvalues can be localized as the extreme points of an appropriately chosen function. By sweeping the frequency range of interest and the boundary of the irreducible first Brillouin zone (FBZ), the band structures can be obtained. Some typical numerical examples with different acoustic impedance ratios and with inclusions of various shapes are presented to validate the proposed method. 相似文献
48.
从换能器技术的变化看声波测井技术的发展 总被引:4,自引:0,他引:4
无论是在电缆测井还是在随钻测井方面,声波换能器结构和振动模式的变化导致了声波测井技术的进步和重大演化.文章以声波测井换能器技术的变化为主线,分析了声波测井技术的发展和进步以及我国在该技术领域取得的进步.单极子声波测井技术已经成为我国成熟的声波测井技术,包括非对称声源技术在内的多极子声波测井技术是我国刚刚攻克的先进声波测井技术并已经进入产业化进程,以井下声波的定向辐射和定向接收为最主要特征的相控声波测井技术是正在研发的新一代声波测井技术,我国在此领域也已经取得显著突破. 相似文献
49.
50.
Sound measured at various points around the environment can be evaluated by a series of multi-pole sources and their acoustic strength can be acquired. In this numerical study, a method, called the inverse method, was examined to achieve this goal. A variety of arrangements of different sources were considered and the acoustic strength of these sources was acquired. Through the application of the mismatch criterion, good conformity was observed between these sound models and the original sound. Furthermore, with regard to results, sound was generated via different source arrangements which showed acceptable agreement with the original sound. Finally, an arrangement named ‘sources vertical arrangement’ was selected as the best approach. 相似文献